Thomcord Grape: Flavorful, Attractive—and Seedless!

Two of America's favorite grapes—Concord, of peanut-butter-and-jelly-sandwich fame, and Thompson Seedless, a summertime classic—are proud parents of a tasty seedless grape called Thomcord.

The plump, juicy Thomcord was developed by the Agricultural Research Service's grape breeders in California.

Thomcord has the blue-black skin, whitish bloom and bold flesh color of the Concord, plus a pleasing Concord-like flavor that's lightened by the sweet, mild taste of its Thompson parent. The fruit is slightly firmer than Concord.

Like Thompson Seedless, Thomcord is well suited for California's sunny vineyards, according to research horticulturist David W. Ramming. He leads the grape-breeding studies at the ARS San Joaquin Valley Agricultural Sciences Center at Parlier, Calif.

Thomcord was the unexpected bonus of a laboratory experiment that Ramming and technician Ronald L. Tarailo conducted in the '80s. Their intent was to hybridize, or cross, a Thompson with a Concord to answer a scientific question about a then-new procedure for breeding superior new seedless grapes. The experiment not only resolved the technical query, but also resulted in a promising plant, A29-67, that is today's Thomcord.

The scientists put A29-67 through 17 years of scrutiny in California vineyards before determining in 2003 that it was ready for growers and gardeners. Already a hit at local farmers' markets during its experimental days, Thomcord may begin showing up at other venues, such as the fresh-fruit section of supermarkets, within a few years. The grape ripens in late July through mid-August.

ARS' grape-breeding research in California dates back to 1923. Over the years, the research has yielded new varieties of red, white and black grapes for hobbyist and professional growers. These fruits of the California studies include some of today's best-selling seedless grapes.

ARS is the U.S. Department of Agriculture's chief scientific research agency